01 March, 2021
Leaf structure and why it matters
Leaves exchange gases via stomata
How stomata work…
Leaf gas exchange impacts the global atmopshere
Vascular tissues in leaves are confined to veins
Transpiration is a by‐product of opening stomatal pores
H2O transport needs to be sufficient to keep stomata open
Venation represents investment in H2O supply
Leaf gas exchange impacts the global atmopshere
Are plants intelligent? Leaf economic theory
Photosynthesis is complicated….
What do plants do when they are hungry?
Photosynthesis is the basis for most life on Earth
- Greek = “building with light”
- Autotroph = “self nourishing”
- Photoautotroph = “self nourishing with light”
- Photosynthesis is an energy pathway
- 2 linked reactions
- light reaction + Calvin cycle
Chloroplasts: Where the magic happens
The nature of light
When light hits chlorophyll a few things can happen
When pigments absorb photons an election gets excited
Photosystems (2) convert light energy to chemical energy
Light reactions: make ATP + NADPH for Calvin cycle
